Background Influenza vaccines require annual readministration; however, several reports
have suggested that repeated vaccination might attenuate the vaccine's effectiveness. We …

Background: The test-negative design is an increasingly popular approach for estimating
vaccine effectiveness (VE) due to its efficiency. This review aims to examine published test …

This report updates the 2018–19 recommendations of the Advisory Committee on
Immunization Practices (ACIP) regarding the use of seasonal influenza vaccines in the …

Vaccines protect recipients by eliciting immune responses and communities by reducing
transmission of infection. However, newer strains with markedly increased transmissibility …

Background There have been inconsistent reports of decreased vaccine effectiveness (VE)
against influenza viruses among older adults (aged≥ 65 years) compared with younger …

Methods for assessing influenza vaccine efficacy and effectiveness have evolved over six
decades. Randomized trials remain the gold standard for licensure, but observational …

Even though the use of SARS-CoV-2 vaccines during the COVID-19 pandemic showed
unprecedented success in a short time, it also exposed a flaw in the current vaccine design …

BACKGROUND: The effectiveness of repeated vaccination for influenza to prevent severe
cases remains unclear. We evaluated the effectiveness of influenza vaccination on …

Annual vaccination with influenza vaccines is recommended for protection against influenza
in the United States. Past clinical studies and meta-analysis, however, have reported …

Background High hemagglutination inhibition (HAI) and neuraminidase inhibition (NAI) titers
are generally associated with reduced influenza risk. While repeated influenza vaccination …